The present invention relates to an apparatus for recording/reproducing of a double-sided optic disk, and more particularly to an apparatus for recording and/or reproducing of a double-sided optic disk wherein information is recorded on and/or reproduced from both sides of an optic disk without transferring an optic pickup from one side to the other side.
Generally, in an apparatus which optically records and reproduces information via an optic disk medium, an optic disk is rotated by a spindle motor at a constant angular velocity or constant linear velocity, and an optic pickup radiates a laser beam while moving along a radius of the rotating optic disk by a transferring device such as a voice coil motor. Here, the laser beam is modulated in accordance with the desired data during the recording of information, and the modulated and reflected beam from the optic disk is detected as an electrical signal during reproducing.
When the optic disk for a general recording/reproducing apparatus is capable of double-sided recording and/or reproducing, after completing the recording and/or reproducing of one side, the disk must be reversed to record/reproduce the other side. However, the reversing of the optic disk is a troublesome and time-consuming chore, which makes the recording and reproducing inconvenient. To successively record and/or reproduce the optic disk without reversing it, an optic pickup may be respectively installed on both sides of the optic disk, which is also unfavorable since this involves excessive cost.
Japanese Laid Open Patent Publication Nos. sho 63-298766, sho 63-302479, Hei 2-21469, Hei 2-287965, and others, describe apparatuses wherein the optic disk is neither reversed, nor is an additional optic pickup installed, to carry out successive recording/reproducing. These apparatuses commonly have a U-shaped guide apparatus for transferring the optic pickup from one side to the other. Also, a rack gear is formed on the U-shaped guide apparatus, and a pinion connected to the rack gear is installed in the pickup. The pinion is driven by a motor mounted together with the pickup. Accordingly, when the pinion is rotated on the rack gear, the entire pickup moves along the U-shaped guide apparatus.
The above structure for transferring the optic pickup from one side to the other side of the optic disk can solve the burdensome cost problem of installing an additional optic pickup. However, the above apparatuses have design and manufacturing problems. After reproducing one side of the optic disk, since the transferring of the optic pickup to reproduce the other side requires a slight amount of time, instantaneous successive reproducing is impossible. Also, since the optic pickup is moved outside the periphery of the optic disk and around to the other side, the surrounding space must be set aside for this operation, which makes miniaturization difficult. Moreover, the accuracy of precisely positioning the optic pickup on both sides of the optic disk, and the mechanical stability requirement for in hanging the optic pickup upside down, present further problems in the design and manufacture of the product.